Talk Title: Peptide Based Liquid-Liquid Coacervates for Biosensing, Degradation Resistance, and as Biofoundries
Dr. Sebastián Díaz, Center for Bio/Molecular Science and Engineering at the U.S. Naval Research Laboratory
Bio: Sebastián Díaz received his Licentiate in Chemistry from the University of Buenos Aires (Argentina) and a Ph.D. in Chemistry from the Georg-August Universität Göttingen (Germany) while working at the Max Planck Institute for Biophysical Chemistry. He is currently a research chemist at the Center for Bio/Molecular Science and Engineering at the U.S. Naval Research Laboratory in Washington, D.C. His research focuses on the functionalization of nanoparticles for probe development, controlling energy transfer pathways at the nanoscale, and interfacing nanotechnology with biology and soft matter for novel materials and catalysis.
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Talk Title: Peptide Probes for Molecular Recognition of C-Reactive Protein: A Combined Study
Dr. Katarzyna Szot-Karpińska, Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
Abstract: We investigate the interactions between C-reactive protein (CRP) and newly developed CRP-binding peptides using biological and physicochemical experiments supported by computational modelling. Three specific CRP-binding peptides (P2, P3, P9) have been identified using M13 phage-display technology. The binding properties of the phage displayed peptides to CRP were demonstrated using biological assays. Fibres of the selected phages/peptides interact differently due to different compositions of amino acid sequences on the exposed peptides, which was confirmed by transmission electron microscopy. Numerical and experimental studies consistently showed that the P3 peptide is the best CRP binder. A combination of theoretical and experimental methods demonstrates that identifying the best binder can be done cheaply and quickly. Such an approach has not been reported previously for peptide screening and demonstrates a new trend in science, where calculations can replace or support laborious experimental techniques. Finally, the best CRP binder – the P3 peptide – was used for CRP recognition on silicate-modified indium tin oxide-coated glass electrodes. The obtained electrodes exhibit a wide operational range (1.0-100 µg mL-1) and a detection limit (LOD = 3σ/S) of 0.34 µg mL-1. The dissociation constant (Kd) of 35 ± 1.2 nM was determined from the change in the current. The selectivity of the obtained electrode was demonstrated in the presence of three interfering proteins [1]. Moreover, the affinity of the P3 peptide for CRP was demonstrated under biologically relevant conditions. The P3 peptide was used as a recognition element in a point-of-care testing sequential microfluidic device. The device was tested with serum, plasma, and whole blood samples to validate its applicability, yielding satisfactory results and a very low limit of detection compared to an antibody-based device on the same platform. These results indicate that the P3 peptide is a promising CRP‑binding ligand that could serve as an alternative to specific antibodies [2].
Bio: Katarzyna Szot-Karpińska received her M.Sc. in chemistry at the University of Warsaw in 2007. She completed a PhD with honours at the Institute of Physical Chemistry, Polish Academy of Sciences (IPC PAS) in 2012. From 2012 to 2014, she was a postdoctoral research associate at the Department of Molecular Biology at the University of Gdansk, Poland. After her postdoc, she joined the Surface Nanoengineering for Chemo- and Bio-Sensors at IPC PAS, where she completed her habilitation in 2024 and is currently an assistant professor. She gained her scientific experience in Germany, France, the United Kingdom, Italy, Slovenia and the United States. She also completed postgraduate studies in 2025, in Organization and Management of Clinical Trials, at Lazarski University, Warsaw, Poland, “Therapeutic peptides in clinical trials”. Her research interests focus on studies on protein-peptide/protein interactions, molecular recognition, and the development of new bioreceptors for biosensors, using biological (phage display technology) and physicochemical (microscopic, spectroscopic and electrochemical) methods.